In the related art, an image forming apparatus including a dew condensation prevention function has been practically used. For example, an electrophotographic image forming apparatus includes a dew condensation preventing control mode which turns ON an exclusive heater for dew condensation prevention to prevent a dew condensation when a main power source is in an OFF state or the apparatus is in a power saving mode such as a sleep mode.
However, the image forming apparatus is configured to continuously apply a current to the exclusive heater in the dew condensation preventing control mode. In the image forming apparatus, the current is continuously applied to the exclusive heater, and thus there is a tendency to consume wasteful power.
Further, the image forming apparatus uses a low-power heater as the exclusive heater, to which the current is continuously applied, so as to slowly warm up the inside of the apparatus in the dew condensation preventing control mode. Thus, the image forming apparatus has a tendency that the inside of the apparatus hardly warms up even in the dew condensation preventing control mode. Accordingly, in the image forming apparatus according to the related art, further dew condensation preventing measures are required.